it's not really a big loss. Science diet isn't really part of the ideal dog food. they contain meal products and mostly fillers that aren't really beneficial to dogs. you should try other dog foods that are so much better than science diet. but what you should remember is that you should store these pet food in quality pet food containers so that you'll maintain it's freshness. check out these pet food containers:  http://www.squidoo.com/petfoodstorage